The use of small plastic identification cards has become increasingly common. Bank or department store credit cards are often used instead of cash or checks in making retail purchases and bank cards are used to perform various banking transactions at automatic tellers. Driver's licenses, specialized identification cards, employee identification, industrial process control, and membership cards are other uses for these plastic cards.
A common feature to all of these cards is that they entitle the owner or possesser of those cards certain privileges. As the use and acceptance of these cards increases, the likelihood and potential gain in counterfeiting or tampering with those cards also increases. Various schemes have been proposed to make plastic card less susceptible to tampering.
U.S. Pat. No. 3,413,171 to Hannon, which issued Nov. 26, 1978, entitled "Process of making identification cards" and U.S. Pat. No. 3,417,497 to Hannon, which issued Dec. 24, 1968, entitled "Identification card" disclose an identification card which is less susceptible to tampering than its predecessors. The card includes a core which is either polyethylene or paper coated on both surfaces by polyethylene. The core is bounded by a polyester envelope which is bonded to the core by polyethylene layers. Identifying indicia is applied to one of the bonded surfaces. During fabrication of the identification card, it is pressure and heat treated so that the polyethylene of the core and the polyethylene adhered to the polyester becomes fused and the indicia becomes suspended within and encased by the fused polyethylene.
When properly formed, the card becomes tamper proof since any attempt to heat or chemically treat the card to gain access to the indicia would result in the ink flowing, giving an indication that the card has been tampered with. While the procedures described in U.S. Pat. No. 3,413,171 and 3,417,497 have achieved some degree of commercial success, in practice the procedures outlined in those patents often are not properly performed with the result that cards become susceptible to tampering.
The failure to achieve tamper proof cards is due to the fact that people who operate the laminating machines which fabricate the cards often do not properly control the temperature and pressure as the card is fabricated. Without proper controls the polyethylene will not fully fuse and the floating effect whereby the ink becomes embedded in the polyethylene is not achieved and printing can be altered or an I.D. photograph can be replaced.
In Europe, bank machine cards have been fabricated each using a layer of so-called "bank note" paper sandwiched between two layers of vinyl. The identifying indicia is applied directly to the note paper and any attempt to tamper with the paper is thought to be readily apparent. The European bank cards, however, exhibit certain shortcomings. These cards tend to peel and split apart. If properly formed, the paper adheres quite nicely to the vinyl layers but is not strong enough to withstand the treatment a typical card receives. The cards tend to split in half rendering them useless for many purposes. If the card gets wet, liquid tends to flow into the paper core, thus accelerating card deterioration.
A vinyl card is subjected to relatively large but naturally occurring temperature variations, other problems are manifested. If a vinyl card becomes too warm, embossments formed in it tend to disappear. As a consequence and as an example, the card becomes ineffective for such purposes as credit charge form imprinting.
When a vinyl card is cold it becomes brittle and is quite susceptible to cracking and splitting. As an example of one consequence, vinyl cards have been known to fail when workers "clock in" on cold mornings. Since many industries now use computerized production control, card failures during clock ins have resulted in part or all of computerized production controls being disrupted.
From the above, it is apparent that there is a need for a tamper proof, long lasting identification card which avoids the difficulties associated with prior identification cards. The card should be flexible, durable and attractive if it is to be accepted by card users and consumers who have been frustrated by the shortcomings of prior identification cards.